A metacercaria from the pink shrimp has been identified as Microphallus sp. (Trematoda, Microphallioae). The metacercaria seems to have a predilection for the ventral cephalothoracic and abdominal musculature, the latter seemingly being the preferred site. Ten live Microphallus cysts from the pink shrimp were fed to a laboratory raised hamster and examination of the hamster 4 days later did not reveal the presence of trematodes. The possible role of sea gulls as predators of the pink shrimp is indicated.